GUILLAUME [IV] de Nevers, son of GUILLAUME [III] Comte de Nevers & his wife Adela --- (-Auxerre 21 Nov 1161, bur Auxerre Saint-Germain). The Origine et Historia Brevi Nivernensium Comitum names "Guillelmum et Renaldum" as the sons of "Guillelmum", son of "Guillelmus…[filius Renaldi]"[2512]. "Willelmus Nivernensis comes" regulated disputes involving "burgis castelli Sancti Germani" in Auxerre, with the consent of "uxor mea comitissa Adalaida et filius meus Guillelmus", by charter dated 1121[2513]. "Guillelmus comes Nivernensis, qui fuit natus de filia Lancelini de Baugenciaco" renounced practices which prejudiced the abbey of Saint-Michel, with the approval of "Adalaidis comitissa uxor ipsius…et filii ipsorum Rainaldus et Robertus…Guillelmus filius supradicti comitis", by charter dated 1134[2514]. "Guillelmum quoque iuuenum Guillelmi Niuernensis consulis filium" is recorded by Orderic Vitalis as one of the supporters of Geoffroy Comte d'Anjou when he entered Normandy 21 Sep 1137[2515]. "Willelmus comes Nivernensis…et filii mei Willelmus et Rainaldus" approved the sale of property by "Hugo de Petrapertusia…Helisabeth uxor mea et Rainaldus frater meus" to the priory of Saint-Etienne by charter dated 1143[2516]. A charter dated Feb 1223 recalls a donation to La Charité-sur-Loire by "domini Guillelmi comitis Nivernensis…cum duobus filiis meis Vuillelmo et Rainaldo" dated 1143[2517]. "Willermus Nivernensis comes" donated property to the Premonstrians at Notre-Dame, with the consent of "Ailleldis comitisse uxoris mee, filiorumque nostrorum, Willelmi et Rainaldi", by charter dated 1144[2518]. "...Milites, Guillelmus filius supra scripti comitis..." witnessed the charter dated 1145 under which "Bernardus Clarevallis...abbas" gave judgment in disputes between Hugues Bishop of Auxerre and "Willelmum comitem Nivernensem"[2519]. He left France with King Louis VII in Jun 1147 on the Second Crusade[2520]. He succeeded his father in 1148 as Comte de Nevers et d'Auxerre. The Historia Vizeliacensis Monasterii names "Nivernensis comes Guillelmus, filius Guillelmi Cartusiensis, filii Renaldi de Hubenc, filii Guillelmi, filii Renaldi, filii Landrici"[2521]. It is assumed that he succeeded as Comte de Tonnerre after the death of his brother in [1148], but the primary source which confirms this has not yet been identified. The Annales Nivernenses record the death in 1161 of "Wilelmus comes, filius Cartusiensis comitis"[2522]. The necrology of the Cathedral of Nevers records the death "XI Kal Dec" of "Guillermus comes Nivernensis"[2523]. The Chronicon of Robert canon of St Maria, Auxerre records the death in 1161 of "Guillelmus Nivernensis comes" and his burial "apud Sanctum Germanum"[2524]. His burial place is referred to in the charter of "Petrus comes Nivernensis et Agnes comitissa uxor eius" dated 10 Jun 1190, under which they agreed to renounce in favour of Saint-Cyr rights previously held by their predecessors, naming "Willelmus comes sepultus in ecclesia sancti Germani Autissiodonrensis…et filius eius Villelmus qui in Bethleem requiescit"[2525].
m (1142 or before) IDA von Sponheim, daughter of ENGELBERT Duke of Carinthia, Marchese of Istria [Sponheim] & his wife Uta von Passau [Ratpotonen] (-25 May 1178, bur Auxerre Saint-Germain). "W Nivernensium comes" granted taxation rights to the church of Autun with the consent of "Ida cometissa et filius meus Guido…[et] Guillelmus filius meus" by charter dated 1158[2526]. Her origin is indicated by Guillaume de Champagne Archbishop of Sens, whose mother was Mathilde von Sponheim, referring to her as matertera[2527]. The Chronicle of Alberic de Trois-Fontaines names "comitissa Mathildis Campaniensis et uxor Renaldi comitis Nivernensis et comitissa Montis Veteris iuxta Coloniam et mater illorum Romanorum qui Froiepain dicuntur" as sisters of "archiepiscopi Coloniensis Frederici"[2528], although the latter is shown by other sources to be their paternal uncle. She is named in an 1142 charter of her husband[2529]. "Guido comes Nivernensis" donated property to the abbey of Corbigny by charter dated [1171] in which he names "frater meus Willelmus", witnessed by "Ida mater mea" and with the consent of "Mathildis uxor mea"[2530].
Comte Guillaume [IV] and his wife had five children